Sequential multiple contact single core switch apparatus utilizing glass enclosed contacts



F. J. BECK SEQUENTIAL MULTIPL March 5, 1-968 3,372,313

E CONTACT SINGLE CORE SWITCH APPARATUS UTILIZING GLASS ENCLOSED CONTACTS Filed Dec. 2, 1964 SW/TC/l ACTUATOR POWER SUPPLY Gill/19470? INVENTOR. F/QA/VC/fi' 4/. BECK ATTORNEY United States Patent SEQUENTIAL MULTIPLE CONTACT SINGLE CORE SWITCH APPARATUS UTILIZING GLASS EN- CLOSED CONTACTS Francis 3. Beck, Philadelphia, Pa., assignor to Honeywell Inc., Minneapolis, Minn, a corporation of Delaware Filed Dec. 2, 1964, Ser. No. 415,254 8 Claims. (Cl. 317-137) ABSTRACT OF THE DISCLOSURE A sequential switching apparatus having glass-enclosed switches positioned between the legs of a U-shaped co e piece. A coil is wound upon the core piece for providing an electromagnetic flux within the core. Each glass-enclosed switch is arranged at a different respective distance from the coil to provide the sequential switching as an electrical signal within the coil varies.

This invention relates to electrical switches. More specifically, the present invention relates to electromagnetically-acutated electrical switches.

An object of the present invention is to provide an improved electromagnetic switch.

Another object of the present invention is to provide an improved electromagnetic switch for sequentially closing a plurality of switch contacts.

A further object of the present invention is to provide an improved electromagnetic switch for sequentially closing a plurality of glass-enclosed switch contacts.

Still another object of the present invention is to provide an electromagnetic switch for sequentially closing a plurality of switch contacts in a non-linear fashion with respect to time.

A still further object of the present invention is to provide an improved electromagnetic switch for opening a plurality of closed switch contacts either simultaneously or in a reverse order, with respect to time, as they were closed.

Still another further object of the present invention is to provide an improved sequential electromagnetic switch, as set forth herein, having a simple operation and construction.

In accomplishing these and other objects, there has been provided, in accordance with the present invention, an electromagnetic switch comprising a plurality of similar glass-enclosed switches arranged at varying distances from a source of actuating magnetic flux by providing a generally U-shaped core structure with an energizing coil thereon. The switches are positioned intermediate the legs of the core at respective distances from the coil to provide corresponding magnetic field reluctance paths at each switch position. The switches are progressively closed when their respective magnetic fields reach a magnitude corresponding to a switch actuating value.

A better understanding of the present invention may be had when the following detailed description is read in connection with the accompanying drawings, in which:

FIG. 1 is a pictorial representation of an electromagnetic switch embodying the present invention.

FIG. 2 is a pictorial representation of a modification of the switch shown in FIG. 1 for non-linear operation.

FIG. 3 is a pictorial representation of a further modification of the switch shown in FIG. 1 for providing adjustment of the switch operating characteristics.

FIG. 4 is a pictorial representation of a still further modification of the switch structure showns in FIGS. 1 and 2 for non-linear operation.

FIG. 5 is a schematic diagram of a function generator using the switch of the present invention.

ICC

Referring to FIG. 1 in more detail, there is shown an electromagnetic switch apparatus embodying the present invention for sequentially actuating a plurality of similar glass-enclosed switches 1. The switches 1 re arranged between the legs of a U-shaped core structure 2 having an energizing coil 3 wound on the base of U-shaped core 2, and connected to an input signal source. In FIG. 2, there is shown a modification of the switch shown in FIG. 1, which modified structure is also used to sequentially actuate a plurality of similar glass-enclosed switches 4. The switches 4 are arranged between the outwardly extending legs of a generally U-shaped core structure 5. However, the legs of the core 5 are arranged with an increasing separation progressing from the base of the U. In FIG. 3, there is shown another modification of the switch shown in FIG. 1 wherein a plurality of glassenclosed switches 7 are positioned between the legs of a U-shaped core structure 8 having an energizing coil 9 wound thereon. Adjacent to each switch 7, a magnetically permeable extension 10 of the core 9 is brought out along a co-extensive path with a respective one of the switches 7. An adjusting screw 11 of magnetically permeable material is provided in a threaded hole in each of the extensions 10 to enable the magnetic reluctance of each extension 10 to be adjusted over a predetermined range.

In FIG. 4, a plurality of glass-enclosed switches 12 are sequentially actuated in a further modification of the switch structure shown in FIG. 1. The switches 12 are afiixed to a non-magnetic support 13, having a tapered cross-section, which is mounted on a fiat surface of a core structure 14 energized by a coil 15. The tapered support is arranged to progressively increase the distance of the switches 12 from the core 14.

In FIG. 5, there is shown a function generator using the switch apparatus of the present invention. A ramp signal generator 20 is provided to supply a characterized energizing signal having an increasing magnitude to the switch actuator 21. The actuator 21 is the energizing coil of the switches shown in FIGS. 1 to 4. The actuator 21 is effective to sequentially actuate the switch contacts 22 in response to the signal from the generator 20. A voltage regulated power supply 23 has a plurality of serially connected resistors 24 connected across an output circuit thereof. The switches 22 are connected between respective ones of the resistors 24 and a common line 25 which line is connected back to one of the supply output terminals. For example, the first of the switches 22 is connected between one output terminal of supply 23 through a first one of the resistors 24 and to the common line 25. The second of the switches 22 is connected between the common line 25 and the junction between the second and third ones of the resistor 24, etc. The effect of sequentially closing the switches 22" is to electrically short the resistors 24 through the common line 25. The return path to the supply 23 includes an output resistor 26 which is connected in series with the resistors 24. As the resistors 24- are shorted by the switches 22, the output signal across the resistor 26 is changed since the current through the resistor 26 is varied. A pair of output terminals 27 are connected across the resistor 26 to supply the varying signal to associated devices. As previously mentioned, the switch actuator 21 and switches 22 are a combined switch apparatus 28, embodying the present invention, as shown in FIGS. 1 to 4.

In operation, the switch of the present invention is effective to sequentially actuate each of the plurality of similar glass-enclosed magnetically-responsive switch contacts. These switch contacts are well known in the art and basically comprise a pair of switch contacts mounted on magnetically-responsive resilient supports and sealed in an evacuated glass tube. The supports are arranged to hold contacts in a normally open condition until a magnetic field is established through the supports and across the contact gap. This field is effective to attract one contact to the other as a result of the bending of the supports to complete a magnetic circuit for the aforesaid field. When the magnetic field is removed, the resilient supports are effective to separate the contacts and reestablish the normally open condition.

As shown in FIG. 1, the switches 1 of the aforesaid glass-enclosed type are arranged between the legs of a U-shaped core stnlcture 2. The energization of the coil 3 by the input signal source is effective to establish a magnetic field in the core 2 which varies in intensity depending on the distance from the coil 3 and the strength of the energizing coil signal. Since the switches 1 are arranged at varying distances from the coil 3, the magnetic reluctance of a flux path between the core 2 and switches 1 will vary from a minimum at the closest switch to a maximum at the farthest switch location. The magnetic field strength necessary to close each of the switches 1 is a predetermined quantity. This field strength is initially achieved, as the input signal to the coil 3 is increased, at a spatial position closest to the coil 3. Thus, the first of the switches 1 will be initially actuated as the energizing input signal is increased from a negligible magnitude. As the energizing signal continues to increase, the first one of the switches 1 will be retained in an actuated, or close-d, condition, and the field strength in the magnetic flux path of the second one of the switches 1 will become sufficient to actuate the second one of the switches 1. This operation will continue with an increasing energizing signal until the farthest one of the switches 1 is actuated while the other switches of switches 1 are retained in their actuated condition. The switches 1 may be either simultaneously opened by a termination of the energizing input signal or sequentially opened in a reverse order from their closing by having the energizing signal from the input signal source slowly decrease to an initial magnitude. Thus, the switch apparatus shown in FIG. 1 is effective to sequentially close the switches 1 and to open them simultaneously or in a reverse sequence from the order of closing.

The switch device shown in FIG. 2 operates substantially in the same manner as discussed above with respect to FIG. 1 with the exception that the legs of the core 5 are tapered outwardly to provide a non-linear time actuation of the switches 4. Thus, for example, it may be arranged that the energizing signal to the coil 6 must double in magnitude to actuate the second switch of the switch 4 and quadruple in magnitude to actuate the second of the switches 4, etc. In such an arrangement, the magnitude of the energizing signal would have to increase in a logarithmic progression using the base of two. Other nonlinear switch-actuating relationships may be provided by suitably shaping the legs of the core 5 to affect the magnetic reluctance at each switch position.

The switch structure shown in FIG. 3 is a modification of that shown in FIG. 1 to allow for individual adjustment of the effect of the magnetic field upon each of the switches 7. Thus, the core 8 is provided with extensions 10 to direct the magnetic field to corresponding ones of the switches 7. The extensions 10 are arranged with threaded holes therein to accommodate magnetically permeable screws 11. By adjusting the position of the screw 11 in the extension 10, the magnetic reluctance of each of the extensions 10 may be controlled to aifect the increase in magnetic flux supplied to respective ones of the switches 7. Accordingly, the actuating magnetic flux for each of the switches 7 may be adjusted with respect to time to compensate for dissimilarities in the operating characteristics of the switches 7.

The switch apparatus shown in FIG. 4 is a modification of the structure shown in FIGS. 1 and 2 to provide non-linear time operation without tapering the legs of the core 14. The switches 12 are mounted on an outside surface of a characterized support of non-magnetic material 13; e.g., plastic. The support 13 which has a tapered crosssection is effective to space the switches 12 from the core 14 in any desired fashion to achieve a non-linear actuation of the switches 12, in a manner similar to that discussed above with respect to FIG. 2. Thus, the switches 12 are affected by the magnetic field from the coil 15 in a nonlinear fashion by having the switch spacing, and the corresponding magnetic reluctance, from the core 14 vary in a predetermined fashion by the support 13. Further, the switches 12 may be positioned on the support 13 to accurately produce the desired switch actuation at a particular point in the magnetic field time gradient produced by coil 15.

The signal generator shown in FIG. 5 is a use of the switch device shown in FIGS. 1 to 4 to sequentially actuate switches 22 by the common actuator 21. For example, using the structure of FIG. 1, the switches 22 would be the glass-enclosed switches 1 and the actuator 21 would be the coil 3 and core 2. The sequential actuation of the switches 22 is effective to vary the signal appearing across the output resistor 26 by sequentially shorting out the resistors 24. Thus, the signal appearing at output terminals 27 may be arranged to vary with respect to time in a linear or non-linear fashion and to decrease abruptly or in a mirror image of the signal increase waveshape.

Accordingly, it may be seen that there has been provided in accordance with the present invention, an electromagnetic switch for sequentially operating glass-enclosed switch contacts while retaining prior operated contacts in an actuated state and having capabilities for non-linear switch contact operation with respect to time and adjustment for operating characteristics of individual contacts.

What is claimed is:

1. A switch apparatus comprising a U-shaped core structure, an energizing coil mounted on said core, and a plurality of magnetically-responsive switch contacts arranged between the legs of said core structure at different respective distances from said coil for providing a sequential operation of said switch contacts as said coil is energized.

2. A switch apparatus as set forth in claim 1 wherein said core structure includes a plurality of core extensions positioned to be co-extensive with said switch contacts, said core extensions each having an adjustable magnetic permeability whereby to vary the magnetic reluctance of a magnetic flux path including said core extensions and respective ones of said switch contacts for providing adjustrnent of said sequential operation of said switch contacts.

3. A switch apparatus comprising a generally U-shaped core structure having the legs of said core arranged in a non-parallel relationship according to a predetermined pattern of magnetic reluctance, an energizing coil mounted on the base of said U-shaped core structure and arranged to produce a magnetic flux in said core, and a plurality of magnetically-responsive switch contacts arranged between the legs of said core structure at diiferent respective distances from said coil.

4. A switch apparatus comprising a U-shaped core structure, an energizing coil mounted on said core to produce a magnetic flux in said core, a non-magnetic support member arranged on an outside surface of said core and a tapered cross-section according to a predetermined pattern for progressively separating an outside surface of said member from said outside surface of said core, and a plurality of magnetically-responsive switch contacts afiixed to said outside surface of said member at positions corresponding to a desired magnetic reluctance of a magnetic flux path through said switch contacts.

5. A switch apparatus comprising a U-shaped core structure, an energizing coil mounted on the base of said core structure to produce a magnetic flux in said core, a signal generator connected to said coil and operative to supply a progressively increasing energizing signal to said coil, and a plunality of magnetically-responsive switch contacts arranged between the legs of said core structure at predetermined respective distances from said coil whereby said switch contacts are progressively actuated by corresponding magnetic field strengths in said core structure.

6. A switch apparatus as set forth in claim 5 wherein said signal generator is arranged to produce a linearly increasing and decreasing continuous ramp signal.

7. A switch apparatus comprising a 'U-shaped core structure, an energizing coil mounted on the base of said core structure to produce a magnetic flux in said core, a signal generator connected to said coil and operative to supply a progressively changing energizing signal to said coil, and a plurality of magnetically-responsive switch contacts arranged between the legs of said core structure at predetermined respective distances from said coil whereby said swtich contacts are actuated by the occurrence of corresponding actuating magnetic field strengths in said core structure.

8. A switch apparatus comprising a generally hollow core structure, an energizing coil mounted on said core structure to produce a magnetic flux therein, input means arranged to receive an input signal, a plurality of magnetically-responsive switch contacts arranged between said hollow of said core structure at predetermined respective distances from said coil, impedance means connected to said magnetically-responsive switch contacts, an energy source arranged to provide energy to said impedance means, and an output means connected to said impedance means and said energy source, whereby an output signal appears at said output means as a predetermined function of said input signal.

References Cited UNITED STATES PATENTS 3,035,136 5/1962 Dal Bianco et a1. 335-152 3,134,908 5/1964 Ellwood 335-452 X 3,188,424 6/1965 Else et a1. 335--152 MILTON O. HIRSHFIELD, Primary Examiner. J. C. SCOTT, Assistant Examiner. 

